One of the great milestones of medicine, as I write in my new book She Has Her Mother’s Laugh, was the discovery that some diseases are inherited–even when the parents of sick children seem perfectly healthy.

These hereditary diseases, known as recessive disorders, manifest themselves when both copies of a gene carry a disabling mutation. They include cystic fibrosis and Tay-Sachs disease. But the most striking of them all is sickle cell anemia. An unusually high number of people in some parts of the world are carriers of the disease, because having a single copy of the sickle cell mutation can actually be good for your health. Continue reading “Friday’s Elk, March 10, 2018” →

In many branches of science, a good clock can make all the difference. The better we can determine how old things are and when events happened, the better we can put the pieces of history back together. It’s important to know that the universe started 13.73 billion years old, for example, and that the Earth is 4.56 billion years old.

There is no one clock to rule them all, though. Each science requires a clock of its own, and some of them require a whole wall of timepieces. For the universe, we have to use old light to tell time. For the Earth, certain radioactive elements like strontium have ticked away accurately since the planet’s formation. Continue reading “Friday’s Elk: February 25, 2018” →